Zero Hour takes place not long after Generals finishes. The GLA has been driven out of China's western border but is now spreading throughout Central Asia and is gaining popularity among the various militias through the media. Intelligence reports they are close to obtaining chemical and biological weapons of mass destruction.

Once again the USA must defend the world from this threat. Meanwhile China remains lurking in the background waiting for its chance to aid the USA when they need it.

The game features new units, structures and abilities as well as new missions and multiplayer maps. Other features include Generals Challenge mode that pits you against nine AI Generals each with their own unique units, style of play and taunts! The Generals SAGE engine has been further enhanced to make your eyes bleed once more.